First appears in: The Metal Wood
The Centrifuge is a "massive cement pipe" running vertically through the city's Under. It is technically described as "an old pipe, one of the biggest in the city. It used to be part of the stormwater runoff system, but the Planners stripped it out years ago and now it’s just empty. It’s the only way up to where we need to be". To navigate it, vehicles must reach extreme speeds so that "centrifugal force will keep the cars pinned to the side" as they drive "sideways" along the inner edge of the pipe.
During a high-speed heist to steal darkprime wood, the experience is described as a "whirling" ride where "the six cars twirled around the massive cement circle, inching upward as they spun, tires screeching slightly as centrifugal force kept them pinned against gravity". Phoenix experiences a moment of terror when her car, heavily weighted with boxes of wood, begins to slip away from the wall toward the "endless darkness" at the bottom of the vertical shaft.